Two configs identical except llm.use_harness and study_id, for the controlled harness-ON vs naive-OFF tuning-trajectory ablation on dense Qwen3.5-27B. Faster substrate (replay_time_scale=0.2, search.high=0.25, max_probes=5) keeps the ablation tractable; Stop-A stays enabled. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>